Drug-resistant 'superbugs' hit 20 states, spread worldwide

Bacteria that are able to survive every modern antibiotic are cropping up in many U.S. hospitals and are spreading outside the USA, public health officials say.

The bugs, reported by hospitals in more than 20 states, typically strike the critically ill and are fatal in 30% to 60% of cases. Israeli doctors are battling an outbreak in Tel Aviv that has been traced to a patient from northern New Jersey, says Neil Fishman, director of infection control and epidemiology at the University of Pennsylvania and president of the Society of Healthcare Epidemiologists.

The bacteria are equipped with a gene that enables them to produce an enzyme that disables antibiotics. The enzyme is called Klebsiella pneumoniae carbapenamase, or KPC. It disables carbapenam antibiotics, last-ditch treatments for infections that don't respond to other drugs.

"We've lost our drug of last resort," Fishman says.

Carbapenam-resistant germs are diagnosed mostly in hospital patients and are not spreading in the community. They're far more common nationwide than bacteria carrying a gene called NDM-1 that made headlines this week, Fishman says.

Those NDM-1 bacteria, named for the city of New Delhi, are rare in the USA and have been found mainly in people who obtain medical treatment in India, Arjun Srinivasan of the U.S. Centers for Disease Control and Prevention (CDC) said Thursday.

Although KPCs are most common in New York and New Jersey, Srinivasan says, "they've now been reported in more than half of the states." A decade ago, only 1% of Klebsiella pneumoniae bacteria reported to CDC by hospitals were carbapenam-resistant. Today, resistance has spread to more than 8% of these bacteria. No one knows precisely how many people have KPC infections because cases aren't routinely reported to the CDC.